David Turner f2dd5dd6eb
Remove DiscoveryPlugin#getDiscoveryTypes ()
With this change we no longer support pluggable discovery implementations. No
known implementations of `DiscoveryPlugin` actually override this method, so in
practice this should have no effect on the wider world. However, we were using
this rather extensively in tests to provide the `test-zen` discovery type. We
no longer need a separate discovery type for tests as we no longer need to
customise its behaviour.

Relates 
2019-02-05 17:42:24 +00:00
..